import React, { Component } from 'react';
import { withRouter } from 'react-router-dom';

class Header extends Component {

    back = () => {
        this.props.history.goBack();
    }

    forward = () => {
        this.props.history.goForward();
    }

    go = () => {
        this.props.history.go(-2);
    }

    render() {
        // console.log('Header组件收到的props是', this.props)
        return (
            <div className="page-header">
                <h2>React Router Demo</h2>

                <button onClick={this.back}>回退</button>&nbsp;
                <button onClick={this.forward}>前进</button>
                <button onClick={this.go}>go</button>
            </div>
        )
    }
}

export default withRouter(Header);

//withRouter可以加工一般组件，让一般组件具备路由组件所特有的API
//withRouter的返回值是一个新组件